Loop system for street-railways.



No. 645,278. I Patented Mar. I3, I900. A. J, THEBBIN; LOOP SYSTEM FOR STREET RAILWAYS.

:(Application filed Jan. 12, 1900.)

(No Model.)

WITNESSES.- W E [NV TOR. g CTW A TTORNE X Ty: NORRIS PEYERs c9. moxoumou WASHINGTON. u. c.

NITED STATES PATENT 0m ALFRED J. TREBBIN, OF CHICAGO, ILLINOIS.

LOOP SYSTEM FOR STREET-RAILWAYS.

SPECIFICATION forming part of Letters latent N 0. 645,278, dated March 13, 1900. 1 Application filed January 12, 1900. Serial No. 1,226. (No model.)

To all whom it may concern:

Be it known that I, ALFRED J. TREBBIN, a citizen of the United States, residing at Chicago, in the county of Gookand State of Illinois, have invented a certain new and useful Loop System for Street-Railways, of which the following is-a specification.

In some large cities, notably the city of Ohicago, Illinois, where the heaviest and principal business section is located within a comparatively-limited area of a few squares, it is customary for the principal street-railway lines, which serve the congested business district, entering the same from some one side or corner, to extend their lines in the form of a loop around said business district with stations or stopping-places every square or two apart, for the greater convenience of patrons whose offices or places of business may be located at various points within or closely adjacent to theinclosed area. Where a considerable number of such outlying roads thus serve the same business district, in order to avoid a multiplicity of tracks, with the consequent encumbering of the streets which would result therefrom, the cars or trains of all those lines which traverse the loop in one direction are caused to use one track around the loop, while the cars of other lines which make the circuit of the loop in the opposite direction are caused to use another and parallel track, or where the cars of all the lines using the loop travel therearound in one and the same direction they are all caused to use a single track, or, at most, where a single track is inadequate, the traffic is divided between a pair of parallel tracks. Where as many as four difierent railway-lines, each operating cars or trains running at close intervals, thus use a common loop, the traffic on said loop becomes considerably crowded and congested, especially during the morning and evening hours when regular patrons of the roads are coming to and returning from their places of business. It is with the purpose of relieving this crowded and congested condition of the trafiic during the busy hours of the day and at the same time allowing each road to serve the full area of the original loop at other hours of the day and night, when desired, that I have devised the subjectmatter of my present invention, which resides, essentially, in

dividing the original loop by a pair of transversely-arranged tracks, preferably between its two longest sides, and a series of suitablyinterposed switches into two smaller adjacent loops, each of which may, whenever desired, be made to accommodate independently onehalf of v the total traffic around the original loop, thus practically doubling the capacity of the original loop.

My invention is diagrammatically illustrated in the accompanying drawing, which represents a centrally-located business area of a city seven blocks or squares long by five wide. The lines marked a, running longitudinally of the figure, may represent streets running north and south, while the shorter lines I), running transversely of the figure, may indicate east and west streets.

As my system has been more especially de signed for use in connection with elevated railways, I shall so hereinafter describe it; but it will be understood that the benefits of my system are by no means confined to elevated railways, but may with great, if not equal, advantagebe applied to surface-roads as well.

Referring again to the drawing, A and A may represent the incoming and outgoing tracks, respectively, of a railway-line which taps the southwest corner of the loop from the west. B and B similarly represent the incoming and outgoing tracks, respectively, of another line which taps the southeast corner of the loop from the south. 0 and C similarly represent the incoming and .outgoin g tracks, respectively, of a third line which taps the northwest corner of the loop from the north, and D and D similarly represent the incoming and outgoing tracks, respectively, of a fourth line which taps the northwest corner of the loop from the west.

Around the entire loop and on opposite sides of the street are a pair of structures carrying parallel elevated tracks, the inner of which tracks I designate by E and the outer by F. These tracks at their various pointsof intersection are of course provided with the necessary frogs and switches to effect the proper travel of trains thereover. In the arrangement shown all trains arriving over the tracks A and 0 travel the loop on the inner track E, while trains arriving over the tracks Ioo' B and D travel the loop on the outer track F. At intervals of every two or three squares stations G and II are located along the tracks E and F, respectively, each station having a platform of a length slightly greater than two trains, the platforms of stations G being each divided into halves g and g, the former platforms serving all trains arriving over the track A and the latter serving all trains arriving over the track 0, while the platforms of stations H are similarly divided into halves h and h, the former serving all trains arriving over the track B and the latter serving all trains arriving over the track D. Between the stations G and H transverse platforms I are located either over or under (here shown as under) the tracks E and F, so that passengers may readily transfer from one line to any of the other three without the necessity of crossing the street on the ground.

A loop system as thus far described is substantially old; but in at least one instance which has come under my observation where the trains of four different lines are all trav: ersing the loop the trains of each line running at very close intervals during the busy morning and evening hours of the day, owing to the necessary crossing of each others tracks at three of the four corners of the loop extreme care has to be exercised in order to prevent interference and accident at these crossings, resultingin unavoidable delays and a consequent inability to operate any where near as many trains on each line as the traffic demands at those hours. The problem of relieving this congestion of traflic by permitting the safe operation of substantially twice as many trains on each line during these busy hours is what I believe I have solved by my present invention, the novel features of which will now be described.

On one of the streets intersecting the loop at or about midway of its longest sides I erect a pair of elevatedstructures, one on each side of the street, extending entirely across the loop and connecting with the structures on the opposite sides thereof. On these structures I lay two pairs of overlapping tracks J, K, L, and M, which at their opposite curved ends have switch-controlled connections with the main tracks E' and F of the loop in the manner shown, orinstead of two pairs of overlapping tracks I may lay a single pair of tracks, one track at its ends having switchcontrolled connection with the main tracks E F on the upper half of the loop and the other track having a similar switch-con trolled connection with the main tracks E F on the lower half of the loop. In practice, however, I prefer to use two pairs of overlapping tracks one track for each of thefourlines, as shownas such an arrangement lessens the number of switches required, and thus facilitates the more rapid movement and closer succession of trains. At suitable points along the line of these loop-bisecting tracks J K and L M, I locate stations N 0, respectively, having double platforms n n and 0 0, respectively, with suitable transverse platforms or crossovers P, all constructed and arranged like the stations on the main linesE F of the loop hereinbefore described. 7

It will thus be seen that by my improvement just described I create an interchangeable single or double loop system. By setting the switches which control the connection of the main-loop tracks E F with the bisecting tracks J, K, L, and M in one way I can send the trains of all four lines around the entire original loop, and by simply setting said switches the other way I can at once create two separate and distinct adjacent loops,with the trains of two lines passing around each loop entirely independent of the trains passing around the other loop. The distinct advantage of such an arrangement is that a train traversingo'ne of the smaller loops has to share the right of way with only one-half as many other trains as when traversing the original large loop. From this it follows that each line can by the change from the single to the double loop system, as described, operate j ust twice as many trains over its own line with the same degree of safety and convenience as on the single loop, which, if carried into effect during the busy morning and evening hours and on holidays and other special occasions when traffic is congested,would result in greatly-increased comfort and convenience to patrons of the roads and increased profits to the roads themselves.

It is to be noted that by reason of the fact that the two smaller loops which may thus be created at pleasure out of the original loop have two sides lying adjacent the same convenience of ready transfer from one line to any of the other three remains in the operation of the double loop exactly as in the op eration of the single loop.

While I have described my present invention with special reference to its adaptation to and utility on elevated railways, it will be understood that it is not limited to use in connection with elevated railways, but may be applied with equal advantage to surface or underground roads as well.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. A loop system for street-railways, comprising a railway-track arranged in the form of a loop, a plurality of separate railway-lines tapping said loop at different points, the trains thereof all traversing said loop in the same direction, and a pair of transversely-arranged tracks bisecting said loop and having switchcontrolled connections with the main track of the loop, whereby theoriginal single loop may at any time be converted into two adjacent independent loops, thereby practically doubling the capacity of the separate lines, substantially as described.

2. A loop system for street-railways, comprising a plurality of parallel railway-tracks arranged in the form of a loop, a plurality of separate railway-lines tapping said loop at difierent points, and transversely-arranged tracks bisecting said loop and having switchcontrolled connections with the main tracks of the loop, whereby the original loop may at any time be converted into two adjacent independent loops, thereby practically doublin g the capacity of each of the separate lines, substantially as described.

3. A loop system for street-railways, comprising a plurality of parallel railway-tracks arranged in the form of a loop, a plurality of separate railway-lines tapping said loop at different points, the trains thereof all traversingsaid loop in the same direction, and transversely-arranged tracks bisecting said loop and having switch-controlled connections with the main tracks of the loop, whereby the original loop mayat any time be converted into two adjacent independent loops, thereby practically doubling the capacity of each of the separate lines, substantially as described.

4. A loop system for street-railways, com prising a pair of parallel railway-tracks arranged in the form of a rectangular loop, a plurality of separate railway-lines tapping said loop at the corners thereof, and transversely-arranged tracks bisecting said loop and having switchcontrolled connections with the two main tracks of the loop, whereby said transversely-arranged tracks may be thrown into or cut out of the system at will, substantially as described.

5. A loop system for street-railways, comprising a pair of parallel railway-tracks arranged in the form of a rectangular loop, a plurality of separate railway-lines tapping said loop at the corners thereof, transverselyarranged tracks bisecting said loop and having switch-controlled connections with the two main tracks of the loop, whereby said transversely-arranged tracks may be thrown into or cut out of the system at will, and a series of transferstations located at intervals along both the main and the transversely arranged tracks of the loop, substantially as described.

In testimony that I claim the foregoing as my invention I have hereto signed my name in the presence of two witnesses.

- ALFRED J. TREBBIN, Vitnesses:

SAMUEL N. POND, EDW. B. WITWER. 

